Retractor

ABSTRACT

A retractor for use in surgical operations comprises a pair of blade assemblies. In operation, the blade assemblies are initially in a closed position to assume a low profile, inserted into a relatively small incision, and stretched apart from each other, thereby stretching the skin about the incision to form an aperture longer than the incision. The retractor is adapted to rotate a first blade about a first axis and a second blade about a second axis. The retractor is adapted to move the pair of blade assemblies apart along a third axis. The retractor is adapted to pivot the first blade about a fourth axis and the second blade about a fifth axis. In some embodiments, a method of performing an operation, e.g. a spinal operation, on a patient using the disclosed retractor is provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/504,581, filed Feb. 16, 2017, which is the U.S. National Phase under35 U.S.C. § 371 of International Application No. PCT/US2015/049211,filed Sep. 9, 2015, titled RETRACTOR, which claims priority benefit toU.S. Provisional Patent Application No. 62/048,639, filed Sep. 10, 2014,the entirety of which is hereby incorporated by reference herein.

FIELD

The present application relates to surgical methods and tools, and moreparticularly to a retractor and a method of operating a retractor.

BACKGROUND

Retractors are surgical devices used to spread bodily tissues in orderto allow a surgeon or surgical assistant to see and access a part of thebody that is to be surgically treated. In general, retractors comprise apair of jaws or blades that grip the bodily tissue and push it apartunder the force generated by an actuator, such as a pair of scissor-likearms having a distal end and a proximal end. The proximal end generallydefines a pair of handles and the distal end attaches to the pair ofblades so that manipulation of the handles causes the blades to moveapart from one another. Once an incision is made in the body to beoperated on, the blades are inserted into the incision and the actuatoris manipulated to move the blades of the retractor apart, thus spreadingthe tissue and providing an aperture through which the surgeon canaccess visualize the tissue to be surgically treated. One problem withthis type of retractor is that the aperture size is generally limited bythe size of the incision, meaning that a large aperture requires arelatively large incision. The drawback to this arrangement is thatlarger incisions result in the need for longer periods for healing ofthe incision. There is thus a need for a surgical retractor that iscapable of creating a relatively large aperture using a relatively smallincision, thereby reducing the invasiveness of the surgical procedure,post-operative healing times and patient discomfort.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the describedembodiments are described with reference to drawings of certainpreferred embodiments, which are intended to illustrate, but not tolimit. It is to be understood that the attached drawings are for thepurpose of illustrating concepts of the described embodiments and maynot be to scale.

FIG. 1 provides a perspective view of an embodiment of a retractor withthe blades in a closed position.

FIG. 2 provides a perspective view of the retractor of FIG. 1 with theblades in a closed position.

FIG. 3 provides a top view of a retractor of FIG. 1 with the blades in aclosed position.

FIG. 4 provides a perspective view of an embodiment of a retractor, withthe blades in an opened position. Opening the retractor along this axisstretches the incision along its length.

FIG. 5 provides a top view of a retractor of FIG. 4 with the blades inan opened position.

FIG. 6 provides a perspective view of the retractor of FIG. 4 in therotated position. Opening the retractor along these axes stretches theincision along its width.

FIG. 7 provides a top view of the retractor of FIG. 6 in the rotatedposition.

FIG. 8 provides a perspective view of the retractor of FIG. 6 in thepivoted position. Opening the retractor along these axes stretches theincision along its width and/or length.

FIG. 9 provides a top view of the retractor of FIG. 8 in the pivotedposition.

FIG. 10 provides a top view of the actuator of FIG. 1.

FIG. 11 provides a perspective view a rotation mechanism of FIG. 1.

FIG. 12 provides a perspective view a rotation mechanism of FIG. 11.

FIG. 13 provides an exploded view of a rotation mechanism of FIG. 1.

FIG. 14 provides a perspective view a pivot mechanism of FIG. 13.

FIG. 15 provides an exploded view of a pivot mechanism of FIG. 14.

FIG. 16 provides a schematic view of a slide mechanism.

FIGS. 17A-17D show the use of a probe to insert a retractor system toform an operative channel through the tissue of a patient to access aportion of the patient's spine.

FIGS. 18A-18D show various embodiments of a probe system which can beused to insert a retractor system to form an operative channel throughthe tissue of a patient.

FIGS. 19A-19I show various cross sections of a probe system.

DETAILED DESCRIPTION

As will be explained below, certain retractor embodiments describedherein provide advantages over the prior art retractors comprising a setof blades and an actuator, such as a set of scissor arms. For example,the retractor of the illustrated embodiment allows a person to insert arelatively compact set of retractor blades into an incision having ashort length. In some embodiments, the compact set of retractor blades(e.g., a first blade, a second blade, a third blade) are of such a sizethat they can be inserted within the incision so that they are snuglyembraced by the side walls of the incision (e.g. a closed position).

In some arrangements, optionally, an actuator causes the first blade andthe second blade to move apart (e.g., to an opened position) in adirection that can be essentially parallel to the length of theincision. This can cause the tissue to stretch in one direction (e.g.,along the length of the incision), creating an opening having a lengthin that direction that is substantially longer than the incision. Oncethe retractor is opened in the first direction, the actuator may belocked open. Optionally, a rotation mechanism on the first and/or secondblades may be manipulated to rotate the blades (e.g., to a rotatedposition), for example, pulling the incised tissue apart in one or moredirections that are not parallel to the incision. Optionally, a pivotmechanism on the first and/or second blades can be manipulated to pivotthe blades (e.g., to a pivoted position), pulling the incised tissueapart in one or more directions that are not parallel to the incision.Optionally, an adjuster on the first and/or second arms can bemanipulated to slide or otherwise translate the arms (e.g., to a slideposition), pulling the incised tissue apart in directions that are notparallel to the incision. In some embodiments, these directions may beperpendicular, substantially perpendicular or oblique to the incision.In certain embodiments, the retractor can be used to open up an aperturethat is substantially longer and/or wider than the incision, and issubstantially larger than would be possible using a prior art deviceand/or in a manner that is easier to use and/or requiring less stepsand/or less complicated steps. In certain arrangements in relativeterms, the surgeon can use a smaller incision, and in some cases a muchsmaller incision, than would have been required with a prior art device.Moreover, in certain arrangements, removal of the retractor, e.g. byclosing the blades, closing the arms and removing the blades from theincision, can allow the incision to relax back to a size that is muchsmaller than would have resulted from use of the prior art retractor. Inaddition, in certain arrangements, steps performed by the surgeon toretract the tissue can be simplified, easier to use and/or involve lesssteps as compared to prior art devices.

The illustrated embodiment will now be further described with referenceto the appended drawings. In FIG. 1 there is shown a perspective view ofa retractor 10 having a body 26. The retractor 10 comprises a first arm12, having a distal end 14 to which can be coupled a first bladeassembly 16 comprising a first blade 18. The first blade assembly 16 caninclude a first rotation mechanism 20 to rotate the first blade 18. Thefirst blade assembly 16 can also include a first pivot mechanism 22 topivot the first blade 18. The first arm 12 has a proximal end 24 whichis coupled to the body 26.

The retractor 10 can include a second arm 32, having a distal end 34, towhich can be coupled a second blade assembly 36 comprising a secondblade 38. The second blade assembly 36 can include a second rotationmechanism 40 to rotate the second blade 38. The second blade assembly 36can include a second pivot mechanism 42 to pivot the second blade 38.The second arm 32 has a proximal end 44 which is coupled to the body 26.

In the illustrated embodiment of FIG. 2, the retractor can include athird blade 46 coupled to the body 26. The third blade 46 can include alongitudinally extending slot 48 sized to accept a probe 400, describedherein. In the illustrated embodiment, the probe 400 can be configuredto be inserted from the tip of the third blade 46 toward the body 26.Other configurations are contemplated. The third blade 46 can include aconnector 50. In the illustrated embodiment, the connector 50 is a maleconnector. The body 26 can include a connector 28, which in theillustrated embodiment is a female connector. The connector 50 of thethird blade 46 coupled with the connector 28 of the body 26 to hold thethird blade 46 stationary in relation to the body 26. In the illustratedembodiment, the third blade 46 is configured to be inserted fromunderneath the body 26. The connectors 50, 28 interlock to securelycouple the third blade 46 to the body. In some embodiments, theconnectors 50, 28 form a snap fit. In some embodiments, the connectors50, 28 make an audible noise when the third blade 46 is coupled to thebody 26. Other configurations for coupling these two components togetherare contemplated, such as, for example reversing the male/femaleconnection and/or permanently connecting the parts and/or forming theparts out of more or less components.

The first rotation mechanism 20 rotates the first blade 18 about a firstaxis 52. The second rotation mechanism 40 rotates the second blade 38about a second axis 54. In the illustrated arrangement, the first axis52 passes vertically or substantially vertically through the first blade18, and the second axis passes vertically or substantially verticallythrough second blade 38. In some embodiments, the first and second axesmay be substantially coplanar with one another. Indeed in someembodiments, the first and second axes are not only coplanar but alsosubstantially parallel to one another. In particular embodiments, thefirst and second axes are coplanar with, parallel to, or at somepre-determined skew angle with respect to one another. As will bedescribed above, various embodiments will be described as“substantially” vertically, parallel, coplanar and/or perpendicular. Insuch embodiments, “substantially” can mean within plus or minus 25degrees from the given orientation, in other embodiments, within plus orminus 10 degrees from the given orientation, and in other embodiments,within plus or minus 5 degrees from the given orientation.

In the illustrated embodiment, the first blade assembly 16 and thesecond blade assembly 36 can translate along a third axis 56 (see e.g.,FIG. 3). In the illustrated embodiment, the first blade assembly 16 andthe second blade assembly 36 can move relative to one another along anarc. In the illustrated embodiment, their general direction of motionrelative to one another, and the direction of motion can be along thecommon third axis 56 that is generally defined by a line passing throughthe first axis 52 and the second axis 54. In other embodiments, thefirst blade assembly 16 and the second blade assembly 36 can rotateabout different axes (e.g., axes that are parallel to each other orslightly skewed). In some examples, the third axis is perpendicular orsubstantially perpendicular to the first axis, the second axis or boththe first and second axes. In particular embodiments, the third axis issubstantially perpendicular or perpendicular to both the first axis andthe second axis. In some embodiments, the third axis is substantiallyperpendicular or perpendicular to the first axis, the second axis orboth the first and second axes. In some embodiments, the third axis isperpendicular or substantially perpendicular to both the first andsecond axes. In some embodiments, the retractor described hereinpossesses a mechanism (e.g., set screw, set pin, clamp, detent, ratchetmechanism etc.) for locking the arms 12, 32 in at least onepredetermined position along the third axis 56.

The first pivot mechanism 22 can pivot the first blade 18 about a fourthaxis 58. The second pivot mechanism 42 can pivot the second blade 38about a fifth axis 60. In some such embodiments, the fourth axis 58 andthe fifth axis 60 may be substantially coplanar or coplanar with oneanother. Indeed in some embodiments, the fourth axis 58 and the fifthaxis 60 are not only coplanar but also substantially parallel orparallel to one another. In particular embodiments, the fourth axis 58and the fifth axis 60 are substantially coplanar with, coplanar with,substantially parallel to, parallel to, or at some pre-determined skewangle with respect to one another.

In the illustrated embodiment, the first blade assembly 16 and thesecond blade assembly 36 can slide along a sixth axis 62 (see e.g., FIG.3). In the illustrated embodiment, the first blade assembly 16 and thesecond blade assembly 36 can move together in a proximal-distaldirection. In other embodiments, the first blade assembly 16 and thesecond blade assembly 36 can slide about different axes (e.g., axes thatare parallel to each other or slightly skewed). In some examples, thesixth axis 62 is perpendicular or substantially perpendicular to thefirst axis 52, the second axis 54, or the third axis 56. In particularembodiments, the sixth axis 62 is substantially perpendicular orperpendicular to both the first axis 52 and the second axis 54. In someembodiments, the sixth axis 62 is substantially parallel or parallel tothe fourth axis 58, the fifth axis 60 or both the fourth and fifth axes.In some embodiments, the retractor described herein possesses amechanism (e.g., set screw, set pin, clamp, detent, ratchet mechanismetc.) for locking the arms 12, 32 in at least one predetermined positionalong the third axis 56. In the illustrated embodiment, through all theadditional movements about the axes 52, 54, 56, 58, 60, 62 the thirdblade 46 can remain stationary and fixed relative to the body 26. Inother words, during all movement of the first blade 18 and the secondblade 38 the third blade 26 can remain immobile. In other embodiments,the third blade 46 can move relative to the first blade 18 and thesecond blade 38. For example, the third blade 46 can move along thesixth axis 62, such as through a carriage system, while the first blade18 and the second blade 38 remain stationary. In another example, thethird blade 46 can pivot relative to the first blade 18 and the secondblade 38. The third blade 46 can be hingedly connected to the body 26and can pivot toward the proximal direction to help create an enlargedaperture in the incised tissue.

The blades 18, 38, 46 may have a variety of configurations. In someembodiments, at least one blade is substantially flat. In someembodiments (e.g., the illustrated embodiment of FIGS. 1-3), at leastone blade is bent or beveled in order to enhance the ability of theblades to lie flat when the blades are in the closed position. Thisarrangement can allow the first and second blades 18, 38 to exert forceon the skin about an incision in opposing directions substantiallyperpendicular to the blade axes and perpendicular or oblique to a corddefined by the points at which the blade axes intersect the arms 12, 32of the retractor 10. In some embodiments, one or more blades 18, 38, 46can be fan shaped.

In some embodiments, two of the blades are of substantially differentsizes in at least one dimension. In some embodiments, the at least twoblades of different sizes are the first blade 18 and second blade 38. Insome embodiments, the at least two blades of different sizes are thefirst blade 18 and the third blade 46. In some embodiments, the at leasttwo blades of different sizes are the second blade 38 and the thirdblade 46. In some embodiments, at least one of the blades 18, 38, 46 isa comb-shaped blade. In some embodiments, at least one of the blades 18,38, 46 is a substantially flat blade. In some embodiments, the retractor10 can include at least one removable blade. In some embodiments, thefirst blade 18 and the second blade 38 are removable. The first blade 18can include a first bridge 95 and the second blade 38 can include asecond bridge 96. The blades 18, 38 can have a variety of lengths ofbridges 95, 96. The bridges 95, 96 can allow the blade 18, 38 to besmaller than the length of the retractor 10.

The blade assemblies 16, 36 can be removed from the arms 12, 32. In somearrangement, it can be convenient to remove the blade assemblies 16, 36in order to expedite sterilization of the blade assemblies 16, 36 and/orin order to exchange one or both blade assemblies 16, 36 for other bladeassemblies (e.g. blade assemblies with different size blades, differentconfiguration of blades, etc.) as discussed in more detail herein.

In FIGS. 1-3, the retractor 10 is shown in the “closed position,”meaning that the first blade 18, the second blade 38, and the thirdblade 46 are aligned and relatively close to one another so as toprovide a smaller cross-sectional area as compared to an “openposition”. While the application uses the phrase “the closed position,”it is understood that one or more positions may be described as closed.For instance, the blades 18, 38, 46 may be aligned, substantiallyaligned, stacked, substantially stacked, close together, relativelyclose together, the first blade 18 encloses the second blade 38, thesecond blade encloses the third blade 46, the first blade 18 enclosesthe third blade 46, one or more blades 18, 38, 46 enclose the probe 400,or any other closed positions.

The first blade 18, the second blade 38, and the third blade 46 can besubstantially parallel or parallel in the closed position. Thelongitudinal axes of the first blade 18, the second blade 38, and thethird blade 46 can be aligned on substantially the same or the sameplane in the closed position. The length of the three blades 18, 38, 46in this configuration can be approximately equal to the length of oneblade, such as the length of the first blade 18. The first blade 18, thesecond blade 38, and the third blade 46 can have a stackedconfiguration. The first blade 18 can be in front (e.g., distal), thesecond blade 38 can be in the middle, and the third blade 46 can be inback (e.g., proximal).

The first blade 18 can have a first rail 64 that aligns one side of theblades 18, 38, 46. The first rail 64 can extend from the proximalsurface of the first blade 18 toward the body 26. The second blade 38can have a second rail 66 that can extend from both distal surface andthe proximal surface of the second blade 38. When viewed from the distalend of the retractor 10 (as shown in FIG. 1), the first rail 64 canextend on the left side of the first blade 18 and the second rail 66 canextend on the right side of the second blade 38. This configurationpermits the first blade 18 to slide relative to the second blade 38without interference of the rails 66, 68. The rails 66, 68 can have awidth equal to the width of the stacked blades 18, 38, 46.

In FIGS. 4-5, the retractor 10 is shown in the “opened position,”meaning that the first blade 18 is translated relative to the thirdblade 46 and the second blade 38 is translated relative to the thirdblade 46. The first blade 18 is moved apart from the second blade 38,while the third blade 46 can remain stationary. The first blade 18, thesecond blade 38, and the third blade 46 can have an overlappedconfiguration in the opened position, as shown. While the applicationuses the phrase “the opened position,” it is understood that one or morepositions may be described as opened. For instance, the blades 18, 38may be slightly spaced apart, greatly spaced apart, overlapping, notoverlapping, adjacent, with a gap between, without a gap between, at anyspaced apart location along the third axis 56, wherein the total lengthin the opened position is greater than the incision length L, or anyother opened positions.

The motion of the first blade 18 can be coupled to the motion of thesecond blade 38 such that actuation of a single actuator moves both thefirst blade 18 and the second blade 38. In other embodiments, each ofthe first blade 18 and the second blade 38 is separately actuated. Thefirst blade 18 can be in front (e.g., distal), the second blade 38 canbe in the middle, and the third blade 46 can be in back (e.g.,proximal). The length L′ of the three blades 18, 38, 46 in thisconfiguration is greater than the length L of one blade, such as thelength of the first blade 18. When viewed from the distal end of theretractor 10 (shown in FIG. 4). The first blade 18 can translate a firstdistance to the left of the third blade 46. The second blade 38 cantranslate a second distance to the right of the third blade 46. Thefirst distance can be equal to the second distance, but need not be. Theconfiguration of the rails 66, 68 permits the first blade 18 totranslate relative to the second blade 38 without interference of therails 66, 68.

FIG. 5 shows the top view of the retractor 10. In the illustratedembodiment, the proximal ends 24, 44 of the arms 12, 32 can be coupledto the body 26. The arms 12, 32 are coupled to the body 26 at the pivot72. The retractor 10 can include an actuator 74. The actuator 74interacts with the arms 12, 32 to spread the arms 12, 32. One embodimentof the actuator is shown in FIG. 10. Depression of the actuator 74, inthe direction of the arrow A in FIG. 5 (i.e., into the page) results inthe arms 12, 32 and therefore the blade assemblies 16, 36 moving apartalong the directional arrows B and C, causing retractor 10 to assume theopened position depicted in FIG. 5. In the illustrated embodiment, thethird axis 56 forms an arc due in part to the pivot 72. The first blade18 will follow an arced path away from the third blade 46. The secondblade 38 will follow an arced path away from the third blade 46. Thefirst blade 18 will follow an arced path in separating from the secondblade 38. In the illustrated embodiment, the first blade 18 and thesecond blade 38 translate when the arms 12, 32 rotate about the pivot72. In the illustrated embodiment, the third axis 56 can besubstantially perpendicular or perpendicular to the first axis 52 andthe second axis 54. The third axis 56 can extend perpendicularly orsubstantially perpendicularly through the first axis 52 and the secondaxis 54.

It is noted that in the embodiment depicted in FIG. 5, the retractor 10comprises a pair of arms 12 and 32 connected via a pivot 72. Otherembodiments of an actuator may be used. For example, scissor-likeactuators are known in the clamp and retractor arts. In some suchembodiments, the actuator comprises a pair of handles (not shown)coupled to the arms 12 and 32. The handles can be roughly parallel andjoined together at a pivot point 72. The handles can be crossed (e.g.scissor-like) handles and joined together at a pivot point 72. It isalso to be understood that when the actuator is a scissor-likeembodiment, the motion of blade assemblies 16 and 36 traverse an arcrather than a straight line upon opening of the retractor 10.Nevertheless, the spatial relationship of the two blade assemblies 16and 36 can be conceptualized as changing along a line described byarrows B and C, which for the purpose of brevity is referred to hereinas an axis, and in particular the third axis 56.

While the illustrated embodiment uses a mechanism for moving the firstblade 18 to the second blade 38 comprising a pair of arms 12, 32 joinedto one another at a pivot 72, other configurations are contemplated. Insome embodiments, the proximal ends 24, 44 of the arms 12, 32 can bejoined in alternative ways to the body 26 such that the movement of thearms 12, 32 is not a pivoting motion about pivot 72. For instance, arms12, 32 can be joined one to another by a cross member (not shown). Thecross member holds the arms 12, 32 in parallel and stabilizes the arms12, 32. One or more arms 12, 32 can be moved along the cross member inorder to translate the first blade 18 away from the third blade 46 andto translate the second blade 38 away from the third blade 46. In suchconfigurations, the first arm 12 linearly translates relative to thesecond arm 32, rather the rotating about the pivot 72. In thisembodiment, the third axis 56 defines a geometric line passing throughand joining the first axis 52 and the second axis 54. The first blade 18follows a straight path away from the second blade 38.

In some embodiments, the retractor described herein possesses a devicefor locking the arms 12, 32 in at least one predetermined position alongthe third axis 56. The device for locking the arms 12, 32 can be aratchet (not shown). The device for locking the arms 12, 32 can be adetent and recess configuration. The device for locking the arms 12, 32can be disposed on the pivot 72 or the cross member (not shown).

The arms 12, 32 may be removed from the body 26. For instance, in theillustrated embodiment, the pivot 72 can be removed to remove the arms12, 32 from the body 26. This may occur at any time, e.g. prior to orduring sterilization of the retractor 10 or during a surgical procedureonce the retractor 10 has been opened. Removal of the body 26 duringsurgery may afford a member of the surgical team greater freedom ofmotion, an improved field of view or both.

Insertion of the blades 18, 38, 46 into an incision in the closedposition (as in FIGS. 1-3) and translating the first blade 18 and thesecond blade 38 to an opened position (as in FIGS. 4-5) results in astretching of the incision along the third axis. This stretchingincreases the length of the incision from a length approximately equalto the length L of a single blade (e.g., the first blade 18) to a lengthL′ greater than the length L of a single blade (e.g., the first blade18). As can be seen in FIGS. 4-5, the retractor 10 is in the openedposition, meaning that the first blade 18 is relatively separated fromthe second blade 38 along the third axis 56. As the blade assembly 16moves along the directional arrow B and blade assembly 36 moves alongthe directional arrow C, they exert force in the direction of lines Band C, respectively.

In FIGS. 6-7, the retractor 10 is shown in the “rotated position,”meaning that the first blade 18 is rotated relative to the third blade46 and/or the second blade 38 is rotated relative to the third blade 46and/or rotated with respect to the third blade 46 in a first position.While the application uses the phrase “the rotated position,” it isunderstood that one or more positions may be described as rotated. Forinstance, the first blade 18 can be rotated at any angle relative to thethird blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°, 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°,105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°, 160°,165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between 30-60°,between 40-70°, between 50-80°, between 60-90°, between 70-100°, between80-110°, etc.), the second blade 38 can be rotated at any angle relativeto the third blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°,30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°,100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°,160°, 165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between30-60°, between 40-70°, between 50-80°, between 60-90°, between 70-100°,between 80-110°, etc.), the first blade 18 can be rotated approximatelythe same angle as the second blade 38, the first blade 18 can be rotateda different angle as the second blade 38, wherein the width W′ in therotated position is greater than the incision width or the width of anyof the blades 18, 38, 46, or other rotated positions.

The width W′ of the three blades 18, 38, 46 in this configuration isgreater than the width W of any one blade, such as the width of thefirst blade 18 and the rail 64. The first blade 18 can rotate in aclockwise direction about the first axis 52. The second blade 38 canrotate in a counterclockwise direction about the second axis 54. Themotion of the first blade 18 can be independent of the motion of thesecond blade 38. In other embodiments, the motion of the first blade 18can be coupled to the motion of the second blade 38 such that rotationis controlled by a single rotation mechanism.

In the illustrated embodiment, the first blade 18 is rotated by a firstrotation mechanism 20 and the second blade 38 is rotated by a secondrotation mechanism 40. In some embodiments and methods of use, the firstblade 18 can rotate in an opposite direction as the second blade 38 suchthat both blades open relative to the third blade 46. The first rotationmechanism 20 can be identical, substantially similar, or a mirror imageof the second rotation mechanism 40. One embodiment of the firstrotation mechanism 20 is shown in FIG. 11-13. Other embodiments arecontemplated for rotating the first and/or second blades (e.g., variouslinkages, hinges and/or cams).

Turning the first rotation mechanism 20 about the first axis 52 in thedirection of adjustment arrow D, results in rotation of the first blade18. Turning the second rotation mechanism 40 about the second axis 54 inthe direction of adjustment arrow E, results in rotation of the secondblade 38, respectively, as depicted in FIG. 7. As shown in FIG. 7,rotating the first blade 18 causes the first blade 18 to exert force inthe direction of direction arrow F, while rotating the second blade 38causes the second blade 38 to exert force in the direction of directionarrow G. In some such embodiments, the first axis 52 and second axis 54may be substantially coplanar with one another. Indeed in someembodiments, the first axis 52 and second axis 54 are not only coplanarbut also substantially parallel to one another. In particularembodiments, the first axis 52 and second axis 54 are coplanar with,parallel to, or at some pre-determined skew angle with respect to oneanother.

In the illustrated embodiment, the first blade 18 is rotated and/or thesecond blade 38 is rotated after the first blade 18 is translatedrelative to the third blade 46 and the second blade 38 is translatedrelative to the third blade 46. Thus, after insertion in an incision ofthe blades 18, 38, 46 in the closed position, the retractor 10 is openedby the first blade 18 and the second blade 38 translating relative tothe third blade 46 along the third axis 56 to achieve the openedposition. Then the first blade 18 is rotated relative to the third blade46 about the first axis 52 and/or the second blade 38 is rotated aboutthe second axis 54 relative to the third blade 46 to achieve the rotatedposition. However, this depicts only some methods of use.

In some methods, the first blade 18 and/or the second blade 38 isrotated before the first blade 18 is translated relative to the thirdblade 46 and the second blade 38 is translated relative to the thirdblade 46. Thus, after insertion in an incision of the blades 18, 38, 46in the closed position, the first blade 18 is rotated about the firstaxis 52 relative to the third blade 46 and/or the second blade 38 isrotated the second axis 54 relative to the third blade 46 to achieve therotated position. Then the retractor 10 is opened by the first blade 18and the second blade 38 translating relative to the third blade 46 alongthe third axis 56 to achieve the opened position. Then, if needed, thefirst blade 18 and/or the second blade 38 is rotated again relative tothe third blade 46 to achieve the rotated position (e.g., anotherrotated position within the broad definition of the “rotated position”).

The rotated position creates and maintains an aperture in the incisedtissue that is wider W′ (i.e. dimensionally larger in a directionperpendicular or oblique to the direction of the incision) than theincision. If the first blade 18 and/or second blade 38 are rotated afterthe blades 16, 38 have been translated relative to the third blade, thenthe retractor 10 creates and maintains an aperture in the incised tissuethat is both longer L′ due to the translation (i.e. dimensionally largerin the direction of the incision,) and wider W′ due to the rotation(i.e. dimensionally larger in a direction perpendicular or oblique tothe direction of the incision) than the incision.

It is to be understood that, while this description is especially aptwhere the incision is a straight line incision of about 0.1 to about 3inches in length, it can apply to any shape of incision (e.g. an arc, asinusoid, etc.) of any length. In particular embodiments, thecontemplated size of the incision is about 0.5 to 2 inches in length andthe blades 18, 38, 46 are appropriately sized so that when the retractor10 is in the closed position the blade blades 18, 38, 46 fit lengthwisewithin the incision without requiring substantial stretching of theincised tissue prior to opening of the retractor 10. Thus, in someembodiments, the blades 18, 38, 46 are sized to snugly fit within theincision when the retractor 10 is in the closed position.

In FIGS. 8-9, the retractor 10 is shown in the “pivoted position,”meaning that the first blade 18 is pivoted relative to the third blade46 and/or the second blade 38 is pivoted relative to the third blade 46.While the application uses the phrase “the pivoted position,” it isunderstood that one or more positions may be described as pivoted. Forinstance, the first blade 18 can be pivoted at any angle relative to thethird blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°, 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°,105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°, 160°,165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between 30-60°,between 40-70°, between 50-80°, between 60-90°, between 70-100°, between80-110°, etc.), the second blade 38 can be pivoted at any angle relativeto the third blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°,30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°,100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°,160°, 165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between30-60°, between 40-70°, between 50-80°, between 60-90°, between 70-100°,between 80-110°, etc.), the first blade 18 can be pivoted approximatelythe same angle as the second blade 38, the first blade 18 can be pivoteda different angle as the second blade 38, wherein the length L″ and/orthe width W″ in the pivoted position is greater than the incision lengthor width or the length or width of any of the blades 18, 38, 46, orother pivoted positions.

The width W″ of the three blades 18, 38, 46 in this configuration isgreater than the width W of any one blade, such as the width of thefirst blade 18 and the rail 64. The length L″ of the three blades 18,38, 46 in this configuration is greater than the length L of any oneblade, such as the length of the first blade 18. The first blade 18 canpivot in a clockwise direction about the fourth axis 58. The secondblade 38 can pivot in a counterclockwise direction about the fifth axis60. The motion of the first blade 18 can be independent of the motion ofthe second blade 38. In other embodiments, the motion of the first blade18 can be coupled to the motion of the second blade 38 such thatpivoting is controlled by a single pivot mechanism. The pivoted positioncreates and maintains an aperture in the incised tissue that is bothlonger L″ (i.e. dimensionally larger in the direction of the incision,)and wider W″ (i.e. dimensionally larger in a direction perpendicular oroblique to the direction of the incision) than the incision.

In the illustrated embodiment, the fourth axis 58 is perpendicular tothe first axis 52. The first blade 18 can rotate about the first axis 52and pivot about the fourth axis 58. This provides at least two degreesof freedom for the first blade 18 and allows the first blade 18 to bepositioned in a variety of locations within the incision. In theillustrated embodiment, the fifth axis 60 is perpendicular to the secondaxis 54. The second blade 38 can rotate about the second axis 54 andpivot about the fifth axis 60. This provides at least two degrees offreedom for the second blade 38 and allows the second blade 38 to bepositioned in a variety of locations within the incision. The fourthaxis 58 and the fifth axis 60 are perpendicular to the third axis 56.The movement along the third axis 56 provides an extra degree offreedom.

In the illustrated embodiment, the first blade 18 is pivoted by a firstpivot mechanism 22 and the second blade 38 is pivoted by a second pivotmechanism 42. The first blade 18 can pivot in an opposite direction asthe second blade 38 such that both blades open relative to the thirdblade 46. The first pivot mechanism 22 can be identical, substantiallysimilar, or a mirror image of the second pivot mechanism 42. Oneembodiment of the first pivot mechanism 22 is shown in in FIGS. 14-15.Other embodiments are contemplated for providing the described pivotingmotions such as, for example, various linkages, cams and/or hinges.

Pivoting the first pivot mechanism 22 about the fourth axis 58 in thedirection of adjustment arrow H, results in rotation of the first blade18. Turning the second pivot mechanism 42 about the fifth axis 60 in thedirection of adjustment arrow I, results in rotation of the second blade38, respectively, as depicted in FIG. 9. Pivoting the first blade 18causes the first blade 18 to exert force in the direction of directionarrow J, while pivoting the second blade 38 causes the second blade 38to exert force in the direction of direction arrow K.

In some examples, the first axis 52 is substantially perpendicular orperpendicular to the fourth axis 58. In particular embodiments, thefirst axis 52 is at some pre-determined skew angle with respect to thefourth axis 58. In some examples, the second axis 54 is substantiallyperpendicular or perpendicular to the fifth axis 60. In particularembodiments, the second axis 54 is at some pre-determined skew anglewith respect the fifth axis 60. In some examples, the third axis 56 issubstantially perpendicular or perpendicular to the fourth axis 58, thefifth axis 60 or both the fourth axis 58 and the fifth axis 60. In someembodiments, the third axis 56 is substantially perpendicular orperpendicular to both the fourth axis 58 and the fifth axis 60. In someembodiments, the third axis 56 is perpendicular or substantiallyperpendicular to the fourth axis 58, the fifth axis 60 or both thefourth axis 58 and the fifth axis 60. In some embodiments, the thirdaxis 56 is perpendicular or substantially perpendicular to both thefourth axis 58 and the fifth axis 60.

In some embodiments, the third blade 46 can be pivoted about a seventhaxis (not shown) that is parallel to the third axis 56 and extends fromnear the connection between the third blade 46 and the body 26. In someembodiments, the connector 28 can have a hinge that pivots the thirdblade 46. The third blade 46 can be pivoted at any angle relative to thevertical plane greater than zero (e.g., 5°, 10°, 15°, 20°, 25°, 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°,105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°, 160°,165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between 30-60°,between 40-70°, between 50-80°, between 60-90°, between 70-100°, between80-110°, etc.). The third blade 46 can be pivoted a same angle or adifferent angle as the first blade 18 and/or second blade 38, whereinthe length L″ and/or the width W″ in the pivoted position is greaterthan the incision length or width or the length or width of any of theblades 18, 38, 46, or other pivoted positions. The seventh axis isdescribed in some embodiments as substantially parallel or parallel tothe third axis 56. In other embodiments, the seventh axis can be at somepre-determined skew angle with respect to the third axis 56.

The width W″ of the three blades 18, 38, 46 in this configuration isgreater than the width W of any one blade, such as the width of thethird blade 46. The length L″ of the three blades 18, 38, 46 in thisconfiguration is greater than the length L of any one blade, such as thelength of the third blade 46. The first blade 18 can pivot in aclockwise direction about the fourth axis 58. The second blade 38 canpivot in a counterclockwise direction about the fifth axis 60. The thirdblade 46 can pivot about the seventh axis toward the proximal direction.The motion of the third blade 46 can be independent of the motion of thefirst blade 18 and the second blade 38. In other embodiments, the motionof the third blade 46 can be coupled to the motion of the first blade 18and/or the second blade 38 such that pivoting is controlled by a singlepivot mechanism. The pivoted position creates and maintains an aperturein the incised tissue that is both longer L″ (i.e. dimensionally largerin the direction of the incision,) and wider W″ (i.e. dimensionallylarger in a direction perpendicular or oblique to the direction of theincision) than the incision.

The third blade 46 can be pivoted by a pivot mechanism that is identicalor substantially similar to the pivot mechanism described herein for thefirst blade 18 and second blade 38. Other embodiments are contemplatedfor providing the described pivoting motions such as, for example,various linkages, cams, hinges, gears and/or levers.

In the illustrated embodiment, the first blade 18 is pivoted and/or thesecond blade 38 is pivoted after the first blade 18 is rotated and/orthe second blade 38 is rotated and after the first blade 18 istranslated relative to the third blade 46 and the second blade 38 istranslated relative to the third blade 46. Thus, after insertion in anincision of the blades 18, 38, 46 in the closed position, the retractor10 is opened by the first blade 18 and the second blade 38 translatingalong the third axis 56 relative to the third blade 46 to achieve theopened position. Then the first blade 18 is rotated about the first axis52 relative to the third blade 46 and/or the second blade 38 is rotatedabout the second axis 54 relative to the third blade 46 to achieve therotated position. Then the first blade 18 is pivoted about the fourthaxis 58 relative to the third blade 46 and/or the second blade 38 ispivoted about the fifth axis 60 relative to the third blade 46 toachieve the pivoted position. In some embodiments, the third blade 46 ispivoted about the third axis 56 toward the proximal direction. However,this depicts only some methods of use.

In some methods, the first blade 18 is pivoted and/or the second blade38 is pivoted and/or the third blade 46 is pivoted before the firstblade 18 and/or the second blade 38 is rotated. In some methods, thefirst blade 18 is pivoted and/or the second blade 38 and/or the thirdblade 46 is pivoted is pivoted before the first blade 18 is translatedrelative to the third blade 46 and the second blade 38 is translatedrelative to the third blade 46.

FIGS. 10-15 show embodiments of the actuator 74, the rotation mechanism20, and the pivot mechanism 22. The actuator 74 is a device fortranslating the first blade 18 and the second blade 38 about the thirdaxis 56. The rotation mechanism 20 is a device for rotating the firstblade 18 about the first axis 52. The rotation mechanism 40 can beidentical, substantially similar or a mirror image of the rotationmechanism 20. The pivot mechanism 22 is a device for pivoting the firstblade 18 about the fourth axis 58. The pivot mechanism 42 can beidentical, substantially similar or a mirror image of the pivotmechanism 22. Other configurations are possible for rotating the bladesas described herein e.g., various levers, knobs, cams, etc.

FIG. 10 shows one embodiment of the actuator 74. The actuator 74comprises a screw 76. The screw 76 can be configured to mate with awasher (not shown) in the body 26. The washer allows the screw 76 torotate without translation (e.g., rotate in place). The actuator 74comprises a block 78. The block 78 has a through lumen 80. In theillustrated embodiment, the through lumen 80 is threaded. In someembodiments the through lumen 80 is not threaded. The through lumen 80is sized to accept the screw 76. The through lumen 80 can include acounter sunk opening sized to accept the head of the screw 76.

The first arm 12 has a first mating surface 82 and the second arm 32 hasa second mating surface 84. The mating surfaces 82, 84 interact with theside surfaces of the block 78. In the illustrated embodiment, the matingsurfaces 82, 84 are ramped or angled inward and the side surfaces of theblock 78 are flat. In other embodiments, the mating surfaces 82, 84 areflat and the side surfaces of the block 78 are ramped or angled inward.Upon rotation of the screw 76, the block 78 traverses along the lengthof the screw 76 toward the body 26 in the direction of arrow A. The sidesurfaces of the block 78 abut and interact with the mating surfaces 82,84 of the arms 12, 32 to exert a force on the arms 12, 32.

In some embodiments, the pivot 72 can include a pivot post 86. The pivotpost 86 extends along a longitudinal axis. As can be seen in FIG. 10,the proximal end 24 of the first arm 12 has a first connecting hole 88sized to accept the pivot post 86 and the proximal end 44 of the secondarm 32 has a second connecting hole (not shown) sized to accept thepivot post 86. Upon rotation of the screw 76, the first arm 12 and thesecond arm 32 rotate about the longitudinal axis of the pivot post 86.The first arm 12 rotates clockwise and the second arm 32 rotatescounterclockwise about the longitudinal axis of the pivot post 86. Thiscauses the first blade assembly 16 and the second blade assembly 36 togenerally translate along a third axis 56.

The retractor 10 can include a spring 94. In the illustrated embodiment,the spring 94 wraps around the pivot post 86. In some embodiments, thefirst connecting hole 88 and/or the second connecting hole are sized toaccept a portion of the spring 94, for instance the portion of thespring that is wrapped around the pivot post 86. In some embodiments,the spring 94 biases the first arm 12 and the second arm 32 in theclosed position. The actuator 74 overcomes this biasing force to pivotthe first arm 12 and the second arm 32 about pivot 72, which causes thefirst blade assembly 16 and the second blade assembly 36 to generallytranslate along a third axis 56. The spring 94 tends to bias the arms 12and 32 together. In other embodiments, the spring 94 biases the firstarm 12 and the second arm 32 apart. This biasing force decreases theforce needed by the actuator 74 to translate the first blade assembly 16and the second blade assembly 36 along the third axis 56.

FIGS. 11-12 are perspective views of the second blade 38 in the closedposition and the rotated position, respectively. FIG. 13 is an explodedview of the rotation mechanism 40. Referring back to FIGS. 1, 6-7, thesefigures depict an embodiment of a second blade assembly 38, whichcomprises the second blade 38. The second blade assembly 36 comprises ahub 98. The hub 98 is coupled to the distal end 34 of the second arm 32.In the illustrated embodiment, the hub 98 houses both the rotationmechanism 40 and the pivot mechanism 42. Also shown in these views isthe second axis 54 to achieve the rotated position. In some embodiments,the second blade 38 is adapted to rotate about the second axis 54. Insome embodiments, this added degree of freedom permit the second blade38 to be rotated outward so that the second blade 38 is farther apartfrom the third blade 46. The third blade 46, in some embodiments,remains stationary. FIG. 6 shows a perspective view of the retractor 10with the first blade 18 and the second blade 38 in a rotated position.FIG. 7 shows a top view of FIG. 6.

The hub 98 can have a first connecting hole 100. The first connectinghole 100 can be non-threaded. The hub 98 is coupled to an inner barrel102. In the illustrated embodiment the inner barrel 102 is integrallyformed with the second blade 38. In other embodiments, the inner barrel102 can be coupled with the second blade 38. The second blade 38 can beconnected to the second bridge 96 which can be connected to the innerbarrel 102. The inner barrel 102 can be sized to be accepted within thefirst connecting hole 100 of the hub 98.

Referring to FIGS. 11-13, the second rotation mechanism 40 can include ascrew 104. The second rotation mechanism 40 can include a collar 106.The collar 106 can include a threaded bore 108 sized to receive thescrew 104. The screw 104 and the collar 106 are sized to be received ina lumen 110 of the inner barrel 102. The inner barrel 102 can have afirst slot 112 and a second slot 114 cut into the upper portion 116 ofthe inner barrel 102. The first slot 112 can be offset 180 degrees fromthe second slot 114. Specifically, the upper portion 116 of the innerbarrel 102 is that portion of the inner barrel 102 above the highestpoint at which the second bridge 96 connects to the inner barrel 102.The first slot 112 and second slot 114 can extend from near the top ofthe inner barrel 102 to the bottom of the inner barrel 102. The slots112, 114 extend diagonally across the upper portion 116. Although twoslots 112, 114 are shown, other configurations are contemplated (e.g.,one slot, three slots, four slots, five slots). The one or more slotsmay have the same slope and extend in the same direction.

The inner barrel 102 can have an engagement groove 118 circumscribingthe inner barrel 102 above the slots 112, 114. The hub 98 can have acomplementary engagement groove 120 circumscribing the connecting hole100. An appropriately sized retention member (not shown) such as ano-ring can be received within the grooves 118, 120. The retention memberallows the inner barrel 102 to rotate but not translate within the firstconnecting hole 100.

The lumen 110 can have an engagement groove 124 circumscribing the lumen110 above the slots 112, 114. The screw 104 can have a complementaryengagement groove 126 circumscribing the head of the screw 104. Anappropriately sized retention member 128 such as an o-ring can bereceived within the grooves 124, 126. The retention member 128 allowsthe screw 104 to rotate but not translate within the inner barrel 102.

FIGS. 11-13 further depict a first connector pin 134 and secondconnector pin 136. The number of pins equals the number of slots. Theconnector pins 134, 136 extend outward from the collar 106. In theillustrated embodiment, the first connector pin 134 is offset 180degrees from the second connector pin 136. Other configurations arecontemplated. The first connector pin 134 is sized to extend through thefirst slot 112 and the second connector pin 136 is sized to extendthrough the second slot 114.

The screw 104 fits within the threaded bore 108 of the collar 106, asdepicted in FIGS. 11-12. In this configuration, the first slot 112 formsa passage through which the first connector pin 134 fits. The secondslot 114 forms a passage through which the second connector pin 136fits. As depicted in FIG. 11, the second blade 38 can be in the closedposition when the first connector pin 134 is at the bottom of the firstslot 112 and the second connector pin 136 is at the bottom of the secondslot 114. In this configuration, as shown in FIG. 4 it is seen that thesecond blade 38, and the third blade 46 stack to form a substantiallyplanar blade set.

One skilled in the art will recognize that rotating the screw 104 cancause the collar 106 to translate up and down. The retention member 128prevents the screw 104 from translating. The connector pins 134, 136 canbe rigidly coupled to the collar 106. At least one connector pin 134 or136 can be retained in the channel 122 of the hub 98, which prevents thecollar 106 from rotating. Rotating the screw 104 will force the collar106 to rise since the screw 104 cannot translate and the collar 106cannot rotate. The connector pins 134, 136 will similarly rise with thecollar 106. As the connector pins 134, 136 rise, they act upon the slots112, 114. Due to the shape of the slots 112, 114, the inner barrel 102will rotate as the connector pins 134, 136 rise. Rotation of the innerbarrel 102 also rotates the second blade 38. In other words, rotatingthe screw 104 forces the connector pins 134, 136 to rise and act uponthe slots 112, 114, thereby causing the inner barrel 102 to rotate, andalso rotate the second blade 38 about the second axis 54. One skilled inthe art will understand that the first blade 18 can be rotated in theother direction (e.g., counterclockwise to close the first blade 18).Starting with the connector pins 134, 136 at the top of slots 112, 114,translating the collar 106 downward will force the connector pins 134,136 to move down the length of the screw 104 in the slots 112, 114,thereby causing the inner barrel 102 to rotate, thereby causing thesecond blade 38 to rotate about the second axis 54.

As can be seen in FIG. 13, the assembly of inner barrel 102, the collar106, the screw 104, and the connector pins 134, 136, fits through thefirst connecting hole 100 of the hub 98. As can be seen in FIGS. 6-7,the head of the screw 104 is visible through the hub 98 allowing thescrew 104 to be manipulated. One of skill in the art will appreciatethat the connector pins 134, 136 engage the slots 112, 114, therebypermitting the inner barrel 102 to freely turn about the second axis 54.The retention member (not shown) prevents the inner barrel 102 frommoving up or down along the second axis 54. The retention member 128 canprevent the screw 104 from moving up or down along the second axis 54.Turning the screw 104 about the second axis 54 in one direction cancause the collar 106 to move upward along the second axis 54, whileturning the screw 104 in the opposite direction can cause the collar 106to move downward along the second axis 54. As explained above, movementof the collar 106 forces movement of the connector pins 134, 136 up anddown the second axis 54. Movement of the connector pins 134, 136 in onedirection can create force in one direction on the slots 112, 114 in theinner barrel 102 causing the inner barrel 102 to rotate. The screw 104can be turned to rotate the second blade 38 toward or away from thethird blade 46. In the illustrated embodiment, the second blade 38 isconnected to a second bridge 96, which in turn is connected to the innerbarrel 102 such that rotating the inner barrel 102 about second axis 54clockwise can result in the second blade 38 also turning to clockwise.

The first blade assembly 16 can be substantially similar to theembodiment described herein. For instance, the first blade assembly 16can include an inner barrel similar to inner barrel 102, screw similarto screw 104, collar similar to collar 106, and connecting pins similarto connecting pins 134, 136. In some embodiments, the first bladeassembly 16 rotates clockwise about the first axis 52 away from thethird blade 46 and the second blade assembly 36 rotates counterclockwiseabout the second axis 54 away from the third blade 46. In thisconfiguration, the inner barrel of the second blade assembly 36 can be amirror image of the first blade assembly 16. For instance, the firstblade assembly 16 can have one slot which is the mirror image of firstslot 112 and another slot which is the mirror image of second slot 114.This slot configuration allows the first blade 18 to rotate clockwise,the opposite direction as the second blade 38 described herein. Thefunction of the connector pins of the first blade assembly 16 and themethod of rotation can be substantially similar.

FIG. 14 is a perspective view of the first blade assembly 16 in thepivoted position. FIG. 15 is an exploded view of the pivot mechanism 22.Referring back to FIGS. 8-9, these figures depict an embodiment of afirst blade assembly 16, which comprises the first blade 18. The firstblade assembly 16 comprises the hub 97. The hub 97 can be similar,identical or a mirror image of the hub 98 described with respect toFIGS. 11-13. The hub 97 is coupled to the distal end 14 of the first arm12. In the illustrated embodiment, the hub 97 houses both the rotationmechanism 20 and the pivot mechanism 22. The hub 97 can have a secondconnecting hole 142 and a third connecting hole 144. The secondconnecting hole 142 can be non-threaded. The third connecting hole 144can be threaded.

The distal end 14 of the first arm 12 can include a post 146. The post146 can be accepted into a bore (not shown) of the hub 97. The post 146of the first arm 12 and the bore of the hub 97 interact to couple thefirst arm 12 to the first blade assembly 16. The post 146 has a roundcross-section but other shapes are contemplated. The post 146 has agroove 150 circumscribing post 146. The groove 150 is along the distalend of the post 146 that extends into the bore. The second connectinghole 142 is sized to accept a pin 152. The upper portion of the pin 152fits within the second connecting hole 142. The lower portion of the pin142 fits within the groove 150 of the post 146.

The distal end 14 of the first arm 12 can include a ledge 154. The ledge154 can be adjacent to a surface of the hub 98. Unlike the post 146, theledge 154 is not accepted into the hub 98. The ledge 154 has asubstantially square cross-section but other shapes are contemplated.The first pivot mechanism 22 can include a screw 156. The screw 156 isaccepted into the third connecting hole 144 which is threaded. Thebottom portion of the screw 156 abuts the ledge 154. The ledge 154prevents the screw 156 from translating when the screw 156 is rotated.

One skilled in the art will recognize that rotating the screw 156 cancause the hub 97 to pivot about the post 146. Rotating the screw 156forces the hub 97 to rise since the screw 156 cannot translate. As thehub 97 rises, the pin 152 will follow the groove 150 of the post 146.Due to the interaction of the pin 152 with the groove 150, the hub 97can pivot about the post 146 when the screw 156 is rotated. Pivoting ofthe hub 97 can result in the pivoting of the inner barrel (identical,similar or a mirror image of inner barrel 102) received in the firstconnecting hole (identical, similar or a mirror image of firstconnecting hole 100). Pivoting the inner barrel 102 can also pivot thefirst blade 18. In other words, rotating the screw 156 will cause thehub 97 to pivot about the post 146, thereby pivoting the inner barrelcoupled to the first blade 18 and the first blade 18. A spring 158 canact upon the hub 97 to bias the hub 97 toward the unscrewed (i.e., nottilted) configuration. One skilled in the art will recognize that thefirst blade 18 can be pivoted in either direction based on the rotationof the screw 154. The longitudinal axis of the post 146 corresponds tothe fourth axis 58.

The second blade assembly 36 can be similar to the embodiments describedherein. For instance, the second blade assembly can include a postsimilar to post 146, a pin similar to pin 152, and a screw similar toscrew 156. In some embodiments, the first blade assembly 16 rotatescounterclockwise about the post 146 and the second blade assembly 36rotates clockwise about a similar post. In some configurations, thesecond blade assembly 36 can be a mirror image of the first bladeassembly 16. For instance, the second connecting hole of the secondblade assembly 36 can be closer to the third blade 46 and the thirdconnecting hole of the second blade assembly 36 can be further away fromthe third blade 46. These configurations of the connecting holes allowthe second blade 38 to pivot in the opposite direction as the firstblade 18 described herein. The function of the pins and the posts of thesecond blade assembly 36 and the method of rotation of the screw can besimilar.

The retractor 10 can be in the “slid position,” meaning that the firstarm 12 and the second arm 32 are displaced in the proximal-distaldirection relative to the third blade 46 along a sixth axis 62. Whilethe application uses the phrase “the slid position,” it is understoodthat one or more positions may be described as slid. For instance, thefirst arm 12 can be slid at any position along the body 26, the secondarm 32 can be slid at any position along the body 26, the first arm 12can be slid approximately the same distance as the second arm 32,wherein the width in the slid position is greater than the incisionwidth or the width of any of the blades 18, 38, 46, or other slidpositions.

FIG. 16 depicts an embodiment of a slide mechanism 162 that provides anadditionally degree of freedom. The slide mechanism 162 can include acarriage 164. The carriage 164 can be attached to the body 26 via atrack 166. In some embodiments, the track 166 can be linear and/orparallel to the width of the blades 18, 38, 46. The track 166 can extendfrom the proximal end of body 26 to the distal end of the body 26, orover a portion therewithin. The first arm 12 and the second arm 32 canbe coupled to the carriage 164. In the illustrated embodiment, the pivot72 can be coupled to the carriage 164. The slide mechanism 162 caninclude an actuator (not shown) that permits the carriage 164 to slidealong the track 166. The track 166 can define the sixth axis 62. In someembodiments, the actuator can include a screw that abuts a proximal endof the carriage 164. Rotation of the actuator causes the carriage 164 totranslate from the proximal end of the body 26 to the distal end of thebody 26 along the sixth axis 62. The slide mechanism 162 permits thearms 12, 32 to extend a greater distance from the distal end of the body26. The slide mechanism 162 permits the first blade 18 and the secondblade 38 to slide relative to the third blade 46. The third blade 46 isnot coupled to the sliding mechanism, but is coupled to the body 26described herein. This permits the first blade 18 and the second blade38 to slide relative to the third blade 46. The slide mechanism 162permits the incision to be stretched along the width of the incision tocreate an opening width greater than width W″.

One skilled in the art will recognize that slide mechanism 162 causesthe first arm 12 and the second arm 32 to slide relative to the body 26.Sliding the first arm 12 and the second arm 32 will also slide the firstblade 18 and the second blade 38. The pivot 72 can be received withinthe carriage 164, allowing the arms 12, 32 to move about the pivot 72and allow the blade assemblies 16, 36 to translate along the third axis56. The actuator 74 can translate the blades 18, 38 irrespective of thelocation of the carriage 164. The rotation mechanisms 20, 40 can rotatethe blades 18, 38 irrespective of the location of the carriage 164. Thepivot mechanisms 22, 42 can pivot the blades 18, 38 irrespective of thelocation of the carriage 164. One skilled in the art will recognize thatthe carriage 164 can slide in either direction.

In some embodiments, the third blade 46 can be coupled to the carriage164 and can be movable relative to the arms 12, 32, which can be coupledto the body 26. Rotation of the actuator can cause the carriage 164 totranslate from the distal end of the body 26 to the proximal end of thebody 26 along the sixth axis 62. The slide mechanism 162 permits thethird blade 46 to move a distance toward the proximal end of the body26, permitting the incision to be stretched along the width of theincision to create an opening width greater than width W″. The pivotmechanism of the third blade 46 can pivot the third blade 46irrespective of the location of the carriage 164. One skilled in the artwill recognize that the carriage 164 can slide in either proximal ordistal directions.

Some embodiments contemplate kits comprising a retractor 10. In someembodiments, the kit comprises a plurality of removable and exchangeableblade assemblies 16, 36. Each blade assembly may comprise a differentactuator, a different rotation mechanism, a different pivot mechanismand/or a different slide mechanism. Each blade assembly may comprise adifferent blade. In some embodiments, the kit comprises at least threeblade assemblies having amongst the three blade assemblies at least twodistinct blade configurations. In other embodiments, the kit comprisesfrom 3 to 12 blade assemblies having amongst the several bladeassemblies from 2 to 12 distinct blade configurations. In someembodiments, the kit comprises at least two pairs of identical,substantially similar, or mirror image blade assemblies. In someembodiments, the kit comprises at least two pairs of mirror image bladeassemblies. In other embodiments, the kit comprises from 2 to 10,especially about 2 to 5 such pairs of blade assemblies.

In some embodiments, the retractor 10 may be provided to a surgeon orsurgical personnel in the form of a kit comprising additional surgicalarticles and optionally instructions for the use and handling of theretractor. Such additional surgical articles may include one or more of:scalpels, suture needles, pedicle screws, suture material, spinalimplant material, spinal fusion rods, biocompatible adhesive and closurestaples.

In some embodiments, the blades 18, 38, 46 are removable. In someembodiments, the blades 18, 38, 46 may take on a variety of shapes andsizes. In some embodiments, a kit is provided comprising a plurality ofretractors having blades of various sizes, shapes or both. In someembodiments, a kit is provided comprising one or more arms and two ormore blade assemblies (optionally of varying blade sizes and/or shapes).In some embodiments, a kit is provided comprising a retractor,optionally more than two blades assemblies, at least two of which differfrom one another in size, shape or both, and one or more pedicle screwsfor performing lumbar surgery. Thus, a variety of surgical kits forperforming surgery, especially back surgery, are contemplated andmethods of using the retractor to perform surgery, especially backsurgery, are contemplated

FIGS. 17A-17D illustrate a probe 400 and a method for its use inconjunction with the retractor 10. FIG. 17A illustrates a probe 400 anda portion of a spine, including a first vertebra 440, a second vertebra450, and a disc 460 disposed between the first vertebra 440 and thesecond vertebra 450. The probe 400 can have a probe body 410, a proximalend 413, a distal end 412, an anchor tip 430, and a distal shoulder 420.The anchor tip 430 can be disposed at the distal end 412 of the probebody 410. The distal shoulders 420 can be located at the distal end 412of the probe 400 at the base of the anchor tip 430. In modifiedembodiments, the probe 400 can have a distal end of a different shape.For example, the distal end 412 can be formed without the shoulder 420and/or without the tip 430 and/or one of both elements can be modifiedin shape.

In some embodiments, the probe 400 can be rectangular in horizontalcross section (i.e., the plane bisecting the probe 400 perpendicular tothe axis formed by the proximal end 413 and the distal end 412). Inother embodiments, the probe 400 can be circular in horizontal crosssection or oval cross section. FIG. 19A-19I illustrate somerepresentative cross sectional shape the probe 400 can have, including:a circle (shown in FIG. 19A); an oval (shown in FIG. 19B); a triangle(shown in FIG. 19C); a flattened oval (shown in FIG. 19D); a thinflattened oval (shown in FIG. 19E); a rounded rectangle (shown in FIG.19F); a thin rounded rectangle (shown in FIG. 19G); a rectangle (shownin FIG. 19H); and a thin rectangle (shown in FIG. 19I). In yet otherembodiments, the probe 400 can be any other appropriate shape, includingbut not limited to square, triangular, and ellipsoid. A rectangularcross-sectional shape can include a shape in which the corners of thedevice are rounded and/or arrangements in which the adjacent sides arenot exactly perpendicular (e.g., plus or minus 10 degrees, 5 degrees, 1degrees or 0.1 degrees from perpendicular) and/or when the sides of theprobe have ridges, bends that deviate 10%, 5%, 1% or 0.1% from the widthor length of a side. FIGS. 18A and 18B illustrate a probe 400 withcircular cross section and a probe 400 with an oval cross sectionrespectively.

In some embodiments, the probe 400 can be constructed out of abiocompatible metal, such as but not limited to stainless steel,titanium, and cobalt chrome moly. In other embodiments, the probe 400can be constructed out of a biocompatible ceramic. In still otherembodiments, the probe 400 can be constructed out of any stiff,biocompatible material, including such classes of materials as metals,ceramics, and polymers, or any combinations thereof.

In some embodiments, the probe 400 can have a vertical length (i.e.,length from the distal end 412 to the proximal end 413) in the range ofabout 5-50 cm, about 6-40 cm, about 7-30 cm, about 7-20 cm and about8-10 cm or any other range which is appropriate to allow the probe 400to function as desired. In some embodiments, the probe 400 can have awidth in its largest, non-vertical dimension, in the range of about 5mm-5 cm, about 6 mm-4 cm, about 7 mm-3 cm, and about 8 mm-2 cm,including about 1.5 cm.

In some embodiments, the distal shoulders 420 can extend horizontally infrom the edges of the probe 400 in the range of about 0.1-5 mm, about0.2-4 mm, about 0.3-3 mm, about 0.4-2 mm, about 0.5-1 mm, and about0.6-0.8 mm. In some embodiments, the external corners where the distalshoulders 420 meet the vertical edges of the probe 400 can be squared.In other embodiments, the external corners where the distal shoulders420 meet the vertical edges of the probe 400 can be rounded or smoothed.In some embodiments, the distal shoulders 420 can be machined flat onthe bottom (particularly in such embodiments in which the probe 400 is ashape other than rectangular). In other embodiments, the distalshoulders 420 can be sharpened across their entire length to form ablade along their entire length. In other embodiments, the distalshoulders can be are sharpened across only a portion of their length toform a blade along only a portion of their length. For example, in someembodiments, only half of each distal shoulder 420 is sharpened (e.g.,either the half of the distal shoulders 420 abutting the anchor tip 430or the half of the distal shoulders 420 abutting the edges of the probe400).

In some embodiments, the anchor tip 430 can extend downward from thedistal end 412 of the probe 400. In some embodiments, the anchor tip 430can be substantially triangular (illustrated in FIG. 17A). In otherembodiments, the anchor tip 430 can be substantially parabolic. In otherembodiments, the anchor tip 430 can be a small cylindrical member, suchas a trocar. In yet other embodiments, the anchor tip 430 can be anyshape which allows anchoring of the probe 400 in tissue. In someembodiments, the edges of the anchor tip 430 can be machined to besubstantially smooth. In other embodiments, the edges of the anchor tip430 can be sharpened to form a blade.

In some embodiments, at least a portion of the vertical edges of theprobe 400 can be sharpened. In some of these embodiments, the portion ofthe edges of the probe 400 which are sharpened can be disposed near thedistal end 412 of the probe 400. As a representative example, 1-5 cm ofthe edges of the probe 400 extending up from the distal end 412 anddistal shoulders 420 can be sharpened to form a blade to facilitateinsertion of the probe 400 into corporeal tissue of a patient.

In operation, the probe 400 can be inserted into a patient, preferablyinto an anchorable location, such as a collagenous tissue, bone, orvertebral disc. FIG. 17A illustrates the probe 400 being inserted into apatient (not fully shown) toward the spine (only a first vertebra 440,second vertebra 450, and disc 460 are illustrated in this representativeexample). The probe 400 illustrated in FIG. 17A is a thin, blade likerectangular probe 400 with a triangular anchor tip 430 and squaredcorners where the distal shoulders 420 meet the edges of the probe 400.The structure of the probe 400 can facilitate its passage throughtissues of a patient (e.g., psoas muscles) which can run parallel to theflat surfaces of the probe. In operation, a physician can select alocation in which he desires to use a retractor 10 to form an operativechannel in the tissues of the patient (the spine will be used in thisexample for illustration purposes only). A location is preferablyselected that provides adequate access to an intervertebral disc space,yet minimizes the risk of injury to the nerves extending from theintervertebral foramen. After the surgeon selects the location forretractor 10 placement, he can make an incision in the skin and insertthe probe 400 by placing the anchor tip 430 against the surface of thepatient and applying pressure to the proximal end 413. The physician canthen continue to apply pressure, thereby pushing the probe 400 throughthe tissue of the patient, until the probe 400 is fully in place. Insome embodiments, an imaging modality can be used during the insertionof the probe 400. As a representative, non-limiting example, X-rayfluoroscopy can be used during insertion of the probe 400 to ensurecorrect placement. Any appropriate imaging modality can be used tomonitor the placement of the probe 400. In some embodiments, a surgeoncan make an incision with another instrument, such as a scalpel, priorto the insertion of the probe 400, into which the probe 400 is inserted.In some embodiments, a K-wire (i.e., guide wire) can first be anchoredat the location for retractor 10 placement. The probe 400 can have apassage extending through its longitudinal length to receive the K-wirewhen the probe 400 is inserted at the surgical location. The K-wireadvantageously provides improved accuracy in placement of the probe 400and can also help stabilize the probe 400 during insertion through thepatient tissue.

FIG. 17B illustrates the probe 400 fully in place in a patient. Theprobe 400 has been inserted into the side of the spinal column (heredefined by a first vertebra 440, a second vertebra 450, and the disc 460between them). FIG. 17B illustrates the placement of the probe 400 in alocation in which the anchor tip 430 can anchor the probe 400. As shownin FIG. 17B, the probe 400 has been inserted into the patient until theanchor tip 430 has sunk at least some distance into the disc 460 betweenthe first vertebra 440 and second vertebra 450. The anchor tip 430 hassunk into the disc 460 up until the distal shoulders 420 of the probe400. The distal shoulders 420 serve in this example to limit thepossible insertion depth of the anchor tip 430 of the probe 400.

FIG. 17C illustrates the third blade 46 of the retractor 10 (asdisclosed herein) and a placed probe 400. The third blade 46 can includea longitudinally extending slot 48 sized to accept the probe 40. Thethird blade 46 can fit substantially closely around the probe 400. Thethird blade can be any type of blade as described above, including butnot limited to a substantially flat blade. An incision I having a lengthL is made in a suitable tissue, such as the skin overlying or inproximity to the lumbar region of the spine.

FIG. 17D illustrates the third blade 46 and placed probe 400 of FIG. 17Cwhere the first blade 18 and the second blade 38 of the retractor 10 intheir closed configuration have been placed near the third blade 46. Theblades 18, 38, 46 will be in their stacked configuration when coupled.The blades 18, 38, 46 are in the closed position and aligned relativelyparallel to one another. The connector 50 of the third blade 46 cancouple with the connector 28 of the body 26. FIG. 17D shows theretractor 10 still in the closed position.

In some methods, the retractor 10 of FIG. 17D is manipulated to achievethe opened position, as shown and described in FIGS. 4-5. In the openedposition, the incision can be stretched along the length of the incisionto pull open the incision. In some methods of use, translation about thethird axis 56 results in the retractor 10 opening: i.e. the first blade18 and the second blade 38 move apart from one another in the generaldirections of directional arrows B, C, respectively. The incision can bestretched open in the direction of the directional arrows B and C sothat it obtains a length L′ greater than length L of the incision.

In some methods, the retractor 10 of FIG. 17D is manipulated to achievethe rotated position, as shown and described in FIGS. 6-7. In therotated position, the incision can be stretched along the width of theincision. Turning the rotation mechanism 20, 40 in the direction of thearrows D and E about the first axis 52 and the second axis 54,respectively results in the rotating of the first blade 18 and thesecond blade 38 respectively, resulting in the widening of the incision.The aperture can be opened to a width W. If the retractor is previouslyopened as shown in FIG. 4-5, then the aperture would provide an accessarea of dimensions L′ by W for surgical personnel to view the operatingfield, to pass instruments, sutures, implants and other surgicalmaterials through the aperture.

In some methods, the retractor 10 of FIG. 17D is manipulated to achievethe pivoted position, as shown and described in FIGS. 8-9. In thepivoted position, the incision can be stretched along the width and/orlength of the incision. Turning the pivot mechanism 22, 42 pivots thefirst blade assembly 16 and second blade assembly 36 in the direction ofthe arrows H and I about the fourth axis 58 and the fifth axis 60,respectively results in the pivoting of the first blade 18 and thesecond blade 38, further stretching the incision. The aperture can beopened to a length L″ and a width W″. The aperture can provide an accessarea of dimensions L″ by W″ for surgical personnel to view the operatingfield, to pass instruments, sutures, implants and other surgicalmaterials through the aperture.

In some methods, the retractor 10 of FIG. 17D is manipulated to achievethe slid position, as shown and described in FIG. 16. In the slidposition, the incision can be stretched along the width of the incision.Moving the sliding mechanism 162 respectively results in the translationof the arms 12, 32, and therefore the translation of the blades 18, 38,causing the incision to open. The aperture A can be opened to a widthwider than width W″.

Reversal of the steps described above results in a final incision havingsubstantially the same length L and essentially no width, like theoriginal incision. By way of comparison, in order for a prior art devicehaving a pair of blades to create such an aperture, the incision wouldhave to have a length L′ or L″ and the blades would have to have a widthof W′ or W″. The present retractor 10 permits the use of a much smallerincision to create the aperture. The present retractor 10 permits lessinvasive surgical methods, quicker and more comfortable recovery fromsurgery and potentially cost savings for the medical coverage provider.

The probe 400 can be removed prior to any of these steps or left inplace during the procedure. The probe 400 can allow a surgeon to easilyand quickly insert a retractor 10 without cutting an incision all theway to the surgery site prior to inserting the retractor 10 into thedesired location to access the surgery site. Rather, the surgeon canquickly and easily insert the probe 400 into the desired location,anchor the probe 400 using the anchor tip 430 in the desired location,slip the third blade 46 of the retractor 10 around the probe 400, andthen simply slip the retractor 10 into place. From this position, thefirst blade 18 and/or the second blade 38 can be moved in any of theways described herein. From this position, the first arm 12 and thesecond arm 32 can be moved in any of the ways described herein.

In some embodiments, the probe 400 comprises at least one electrode,wherein the at least one electrode is capable of stimulating a nerve toprovoke an electromyographic response in the nerve. FIG. 18C illustratesa probe 400 with an electrode 431 disposed at the distal end 412 of theprobe 400 on the anchor tip 430. In some embodiments, only one electrodeis used. In other embodiments, a plurality of electrodes can be used,including about 1-10 electrodes, about 2-8 electrodes, about 3-6electrodes and about 4-5 electrodes. In some embodiments, at least oneelectrode can be disposed on the anchor tip 430. In some embodiments, atleast one electrode can be disposed on the probe body 410. The electrode431 can be allowed to any of the embodiments described herein.

In some embodiments, the probe 400 comprises an endoscope 499, whereinthe endoscope 499 can comprise an imaging element 432 at the distal end412 of the endoscope 499 as shown in FIG. 18D. In some of theseembodiments, the endoscope 499 can be configured to both allow a surgeonto visualize the placement of the probe 400 as well as allow a surgeonto slide a retractor 10 down over the probe 400 and into place asdescribed herein to create an operative channel. In some embodiments,the endoscope 499 can include an anchor tip 430. Such an endoscope canbe applied to any of the embodiments described herein.

While certain embodiments have been shown and described herein, it willbe obvious to those skilled in the art that such embodiments areprovided by way of example only. Numerous variations, changes, andsubstitutions will now occur to those skilled in the art withoutdeparting from the invention. It should be understood that variousalternatives to the embodiments described herein may be employed. It isintended that the following claims define the scope of the invention andthat methods and structures within the scope of these claims and theirequivalents be covered thereby.

Further Features of this Disclosure are Given in the Following NumberedClauses:

Clause 1. A retractor comprising:

a first blade,

a first rotation mechanism that rotates the first blade about a firstaxis,

a second blade,

a second rotation mechanism that rotates the second blade about a secondaxis,

a first pivot mechanism that pivots the first blade about a fourth axis,wherein the fourth axis is skewed to the first axis;

a second pivot mechanism that pivots the second blade about a fifthaxis, wherein the fifth axis is skewed to the second axis.

Clause 2. The retractor of clause 1, wherein the first and second axesare substantially coplanar with one another.

Clause 3. The retractor of clause 2, wherein the first and second axesare coplanar with one another.

Clause 4. The retractor of clause 1, further comprising an actuator thattranslates the first blade and second blade about a third axis.

Clause 5. The retractor of clause 4, wherein the third axis issubstantially perpendicular to the first axis, the second axis or boththe first and second axes.

Clause 6. The retractor of clause 4, wherein the third axis issubstantially perpendicular to both the first axis and the second axis.

Clause 7. The retractor of clause 4, wherein the third axis isperpendicular to the first axis, the second axis or both the first andsecond axes.

Clause 8. The retractor of clause 4, wherein the third axis isperpendicular to both the first and second axes.

Clause 9. The retractor of clause 4, further comprising a device forlocking the first and second blades in at least one predeterminedposition along the third axis.

Clause 10. The retractor of clause 1, further comprising an actuatorthat slides the first blade and second blade about a sixth axis.

Clause 11. The retractor of clause 10, wherein the sixth axis issubstantially perpendicular to the first axis, the second axis or boththe first and second axes.

Clause 12. The retractor of clause 10, wherein the sixth axis issubstantially perpendicular to both the first axis and the second axis.

Clause 13. The retractor of clause 10, wherein the sixth axis isperpendicular to the first axis, the second axis or both the first andsecond axes.

Clause 14. The retractor of clause 10, wherein the sixth axis isperpendicular to both the first axis and the second axis.

Clause 15. The retractor of clause 10, wherein the sixth axis issubstantially parallel to the fourth axis, the fifth axis or both thefourth and fifth axes.

Clause 16. The retractor of clause 10, wherein the sixth axis issubstantially parallel to both the first axis and the second axis.

Clause 17. The retractor of clause 10, wherein the sixth axis isparallel to the fourth axis, the fifth axis or both the fourth and fifthaxes.

Clause 18. The retractor of clause 10, wherein the sixth axis isparallel to both the first axis and the second axis.

Clause 19. The retractor of clause 10, further comprising a device forlocking the first and second blades in at least one predeterminedposition along the sixth axis.

Clause 20. The retractor of clause 1, further comprising an actuatorthat translates the first blade and second blade about a third axis andan actuator that slides the first blade and second blade about a sixthaxis.

Clause 21. The retractor of clause 20, wherein the sixth axis issubstantially perpendicular to the third axis.

Clause 22. The retractor of clause 20, wherein the sixth axis isperpendicular to the third axis.

Clause 23. The retractor of clause 20, further comprising a device forlocking the first and second blades in at least one predeterminedposition along the sixth axis.

Clause 24. The retractor of clause 1, further comprising a third bladethat remains stationary during movement of the first blade and thesecond blade.

Clause 25. The retractor of clause 24, wherein the first and thirdblades are of different sizes in at least one dimension.

Clause 26. The retractor of clause 24, wherein at least one of thefirst, second and third blades is a flat blade.

Clause 27. The retractor of clause 1, further comprising a third bladeand a third pivot mechanism that pivots the third blade about a seventhaxis, wherein the seventh axis is skewed to the fourth axis.

Clause 28. The retractor of clause 1, wherein at least one blade isremovable.

Clause 29. The retractor of clause 1, wherein the first and secondblades are removable.

Clause 30. A retractor blade assembly, comprising:

a first blade having attached thereto a first barrel, the first barrelhaving a wall and defining a first lumen, a first slot in the wallhaving a first slope,

a first screw having an axis, the first screw fitting within the firstlumen of the first barrel

a collar having an inner surface configured to mate with the outersurface of the first screw, the collar having a hole that aligns withthe first slot in the wall of the first barrel;

a connecting pin fitting through the hole and the slot such thatmovement of the collar along the axis causes the first barrel to rotatein a first direction; and

a hub comprising a first connecting hole, wherein the first barrel fitswithin the first connecting hole.

Clause 31. The blade assembly of clause 30, wherein the hub is adaptedto be removably affixed to an arm of a retractor.

Clause 32. The blade assembly of clause 30, wherein the hub comprises asecond connecting hole and a third connecting hole, wherein theretractor blade assembly further comprises a second screw configured tobe received within the third connecting hole, a pin configured to bereceived within the second connecting hole, wherein movement of thesecond screw causes the hub to rotate about a post.

Clause 33. A retractor blade assembly, comprising:

a first blade having attached thereto a first barrel,

a hub having a second connecting hole and a third connecting hole,

a second screw configured to be received within the third connectinghole;

a pin configured to be received within the second connecting hole; and

a post extending into the hub, the post comprising a groove configuredto accept the pin;

wherein movement of the screw causes the hub to rotate about the post.

Clause 34. The blade assembly of clause 33, wherein the hub is adaptedto be removably affixed to an arm of a retractor.

Clause 35. The blade assembly of clause 33, wherein the hub comprises afirst connecting hole, wherein the first barrel fits within the firstconnecting hole, the first barrel having a wall and defining a firstlumen, a first slot in the wall having a first slope, a first screwhaving an axis, the first screw fitting within the first lumen of thefirst barrel, a collar having an inner surface configured to mate withthe outer surface of the first screw, the collar having a hole thataligns with the first slot in the wall of the first barrel, and aconnecting pin fitting through the hole and the slot such that movementof the collar along the axis causes the first barrel to rotate in afirst direction.

Clause 36. A retractor, comprising:

a first arm having a distal end and a proximal end;

a second arm having a distal end and a proximal end;

a first blade coupled near the distal end of the first arm;

a first rotation mechanism that rotates the first blade about a firstaxis;

a second blade coupled near the distal end of the second arm rotatableabout a second axis;

a second rotation mechanism that rotates the second blade about thesecond axis, wherein the first axis is substantially parallel to thesecond axis;

a first pivot mechanism in mechanical communication with the first bladeand adapted to pivot the first blade about a fourth axis, wherein thefirst axis is skewed to the fourth axis; and

a second pivot mechanism in mechanical communication with the secondblade and adapted to pivot the second blade about a fifth axis, whereinthe second axis is skewed to the fifth axis.

Clause 37. The retractor of clause 36, further comprising a third bladeand a third pivot mechanism in mechanical communication with the thirdblade and adapted to pivot the third blade about a seventh axis, whereinthe seventh axis is skewed to the fourth axis.

Clause 38. A retractor, comprising:

a first arm having a distal end and a proximal end;

a second arm having a distal end and a proximal end, at least the distalend of the first arm and the distal end of the second arm being movabletoward and away from each other;

a first blade attached near the distal end of the first arm and a devicefor moving the first blade about a first axis to adopt at least anopened position and a closed position;

a second blade attached near the distal end of the second arm and adevice for moving the second blade relative a second axis different fromthe first axis to adopt at least an opened position and a closedposition; and

a device for moving at least the distal end of the first arm and thedistal end of the second arm relative to one another along a third axisthat is not parallel to the first and second axes.

Clause 39. A retractor blade assembly, comprising:

a first arm having a distal end and a proximal end;

a second arm having a distal end and a proximal end, at least the distalend of the first arm and the distal end of the second arm being movabletoward and away from each other;

a first blade attached near the distal end of the first arm and a devicefor pivoting the first blade about a fourth axis;

a second blade attached near the distal end of the second arm and adevice for pivoting the second blade relative a fifth axis differentfrom the fourth axis; and

a device for moving at least the distal end of the first arm and thedistal end of the second arm relative to one another along a third axisthat is not parallel to the fourth and fifth axes.

Clause 40. A method of using a retractor, comprising:

rotating a first blade of a retractor about a first axis;

rotating a second blade of a retractor about a second axis, wherein thefirst axis is substantially parallel to the second axis;

translating the first blade and the second blade about a third axis

pivoting the first blade about a fourth axis, wherein the fourth axis isskewed to the first axis; and

pivoting the second blade about a fifth axis, wherein the fourth axis isskewed to the second axis.

Clause 41. A method of using a retractor, comprising:

making an incision in a tissue of a body;

providing a retractor;

rotating a first blade of a retractor about a first axis;

rotating a second blade about a second axis, wherein the first axis issubstantially parallel to the second axis;

pivoting the first blade about a fourth axis, wherein the fourth axis isskewed to the first axis; and

pivoting the second blade about a fifth axis, wherein the fifth axis isskewed to the second axis.

Clause 42. The method of Clause 41, further comprising positioning thefirst and second blades substantially parallel to each other to form afirst closed blade assembly.

Clause 43. The method of Clause 41, further comprising positioning athird blade substantially parallel to the first and second blades in aclosed position.

Clause 44. The method of Clause 43, further comprising pivoting thethird blade about a seventh axis, wherein the seventh axis is skewed tothe fourth axis.

Clause 45. The method of Clause 43, further comprising inserting thefirst blade, the second blade, and a third blade within the incision.

Clause 46. The method of Clause 41, further comprising actuating theretractor such that the first blade and second blade are moved apartfrom one another along a third axis and the incision is stretched alongthe length of the incision to create an opening longer than theincision.

Clause 47. The method of Clause 41, further comprising actuating theretractor such that the first blade and second blade are slid togetheralong a sixth axis and the incision is stretched along the width of theincision to create an opening wider than the incision.

Clause 48. The method of Clause 41, further comprising creating anaperture in the tissue that is longer and wider than the incision.

What is claimed is:
 1. A retractor comprising: a first flattened blade;a first rotation mechanism configured to rotate the first flattenedblade about a first axis; a second flattened blade; a second rotationmechanism configured to rotate the second flattened blade about a secondaxis; a first pivot mechanism configured to pivot the first flattenedblade about a fourth axis, wherein the fourth axis is skewed to thefirst axis; a second pivot mechanism configured to pivot the secondflattened blade about a fifth axis, wherein the fifth axis is skewed tothe second axis; and wherein the first flattened blade and the secondflattened blade have a stacked configuration to form a substantiallyplanar blade set.
 2. The retractor of claim 1, wherein the firstflattened blade comprises a first rail, wherein the first flattenedblade is configured to slide relative to the second flattened bladewithout interference of the first rail.
 3. The retractor of claim 1,wherein the first flattened blade comprises a first rail and wherein thesecond flattened blade comprises a second rail, wherein the firstflattened blade is configured to slide relative to the second flattenedblade without interference of the first rail and the second rail.
 4. Theretractor of claim 1, further comprising a third flattened blade.
 5. Theretractor of claim 4, wherein the first flattened blade, the secondflattened blade, and the third flattened blade have a stackedconfiguration.
 6. The retractor of claim 4, further comprising a thirdpivot mechanism that pivots the third flattened blade.
 7. A retractorcomprising: a first blade; a first rotation mechanism configured torotate the first blade about a first axis; a second blade; a secondrotation mechanism configured to rotate the second blade about a secondaxis; a first pivot mechanism configured to pivot the first blade abouta fourth axis, wherein the fourth axis is skewed to the first axis; asecond pivot mechanism configured to pivot the second blade about afifth axis, wherein the fifth axis is skewed to the second axis; andwherein the first blade and the second blade are substantially parallelin a closed position with the first blade in front of the second blade,wherein the first blade and the second blade have a stackedconfiguration to form a substantially planar blade set.
 8. The retractorof claim 7, wherein the first blade comprises a first rail, wherein thefirst blade is configured to slide relative to the second blade withoutinterference of the first rail.
 9. The retractor of claim 7, wherein thefirst blade comprises a first rail and wherein the second bladecomprises a second rail, wherein the first blade is configured to sliderelative to the second blade without interference of the first rail andthe second rail.
 10. The retractor of claim 7, further comprising athird blade.
 11. The retractor of claim 10, wherein the first blade, thesecond blade, and the third blade are substantially parallel in theclosed position.
 12. The retractor of claim 10, further comprising athird pivot mechanism that pivots the third blade.
 13. A method of usinga retractor, comprising: making an incision in a tissue of a body;providing a retractor, wherein the retractor comprises a first blade anda second blade, wherein the first blade and the second blade aresubstantially parallel and overlapping in a closed position, wherein thefirst blade and the second blade have a stacked configuration to form asubstantially planar blade set; actuating the retractor to move the oneor more of the first blade and the second blade, wherein actuating theretractor comprises moving the first blade, moving the second blade, ormoving both the first blade and second blade.
 14. The method of claim13, wherein moving the first blade comprises rotating the first blade.15. The method of claim 13, wherein moving the second blade comprisesrotating the second blade.
 16. The method of claim 13, wherein movingthe first blade comprises pivoting the first blade.
 17. The method ofclaim 13, wherein moving the second blade comprises pivoting the secondblade.
 18. The method of claim 13, wherein moving both the first bladeand the second blade comprises translating the first blade and thesecond blade.
 19. The method of claim 13, wherein moving both the firstblade and the second blade comprises linearly translating the firstblade and the second blade.
 20. The method of claim 13, furthercomprising a third blade, wherein the first blade, the second blade, andthe third blade are substantially parallel and overlapping in the closedposition.